US Patent 7251532 Medical lead fixation

A distal tip coupled to a body of an implantable medical device includes a canted passageway extending distally from a lumen of the body and an opening terminating the passageway and positioned in proximity to a distal end of the distal tip; a helical fixation element coupled to an elongated member extending within the lumen of the body is adapted to deflect along the canted passageway of the distal tip. The elongated member is adapted to move the helical member through the passageway of the distal tip and out from the opening and to rotate the helical element thereby affixing the helical element into an implant site.